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Just curious at what is your normal operating oil temperature for the rest of you.
In the 90 degree temps down here today, on my freshly rebuilt engine with newer model fan and offset fan shroud and oil cooler, after driving 5 miles mine says 230 degrees on the gauge and stays there when riding along 50-55 mph. but I have no idea how accurate that gauge or sender is. Oil pressure is fine at 40 psi., using regular dino oil. That seems to a little hot but it may be in the acceptable range for this 1600DP engine. It was suggested at the first oil change after checking valve clearances and everything else, to switch to synthetic, which could possibly lower the operating temp 10-15 degrees, but there are all sorts of differing opinions on this.
What temps do you other guys run?According to Rob & Dave’s Aircooled VW web site, Gene Berg says 235 is the upper limit.
http://www.vw-resource.com/overheating.html
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
In the 100 degree temps we have been running lately My oil temp seems to peak about 218-220 at 55mph, but eases down fairly quick to 205-210 when I back down on the speed. It also takes more than 5 miles to reach that temp. Im using Brad Penn 10-30 partial syntetic oil. Im not sure how much heat dino oil will take before it starts to cook. You may need to confirm your gage. you might not be running the temps you think. Try using an inrfared thermometer pointing at your oil sump after a run and see if your gage and thermometer are close. You can also read head temps and see just how hot that exaust is getting. Im not sure how accurate the following numbers are, but I see them posted on the Samba quite often.
180? to 210? is normal
210? to 230? is warm
230? to 240? is HOT
250? is turn it off &nb sp; &nb sp;Went back to the mechanic who did the engine work, a 10 mile ride, and wouldn’t you know it, the gauge wouldn’t register anything at all on the way over there, but checking the engine case and oil pan at various places with an infrared thermometer read the highest at 194, so it’s not overheating, ambient temp around 80-85 then. Rode home, then on the way the gauge went up to 230 again, 2 min later read 180. So I guess I have to troubleshoot the wiring and the sender and then the gauge to be able to monitor what’s happening. I also have to check if my sending unit and gauge are compatible. Something else to do one of these days to keep me occupied.
Funny, on the way home I was racing the oncoming rain and had to drive through a light shower. The wipers clean off the front of the windshield OK but the inside driver’s side gets coated with droplets, so you need wipers on the inside too. The sweep of the body lines on either side of the dash funnel all the water on the hood around the windshield right inside over the tops of the doors. Can’t ride these things very well in the rain with the top down.mrlmd40764.4738541667
Mrlmd I am glad to see you arent having a heat problem and its more likely the sender/gage. That is why I suggested the infrared thermometer. You had said “after driving 5 miles mine says 230 degrees on the gauge” and I would think from a cold start you should be able to drive 5 miles in death valley and not hit 230. The infrared thermometer is a nice tool to have. I bought one myself from harbor freight for around $30 on sale and it seems to be as accurate as my son in laws high dollar model. I like many others here have oil temp and pressure gages and some even have head temp gages. I do admit I like to know what is going on with my engine, but when you think about the original bug the car is based on having only one idiot light and cruising all day at highway speeds I wonder if we worry too much and miss some of the enjoyment of the drive. I hope you are able to trace down your gage/sender problem with ease and get back to trouble free cruising.
I think the gauge is OK. Just to educate people how this works (google is your friend) – With the ignition key on but engine not running, if I take the wire off the temp sending unit (thermocouple) on the bottom of the oil pan and short it to the block, the gauge reads full scale as it’s supposed to. I have to test the resistance of the sending unit, maybe tomorrow if it doesn’t rain again. There should be at least a 200 ohm difference between cold and hot reading, if not the sensor’s bad and needs replacement. I cleaned up the dirty contact on my sending unit, so maybe that will do the trick when I look at it again tomorrow. It’s a cheap part to replace, $12-15 or so, not too messy but I guess there will be some oil spilling out when and if I have to change it.
And M&S, I totally agree with you about worrying too much and missing out on the ride, but I just had this whole engine rebuilt because of the overheating problem that destroyed the PO’s one in this car, and I don’t want to do that again. Peace of mind knowing everything’s alright to me also adds to the enjoyment of the ride, knowing you can get there and back trouble free.
FYI – Harbor Freight has a laser infrared sensor for about $18 which seems to get good reviews on their site. Maybe I’ll pick one up just to have another tool in the bucket for who knows when you’ll ever need it.mrlmd40764.878275463
mrlmd,
On my Ghia I have an adapter fitting where the oil pressure fitting goes on the side of the engine case. One part of the fitting has the oil pressure sensor and the other end of the adapter has the temp sensor. Oddly enough, the instructions that came with my gauge kit says to install the oil temp sensor in place of the plug for the oil pressure relief spring. Not to sure I like that so much. Anyway…was wondering if the oil temp is cooler up where the pressure sensor is than in the bottom of the engine. Something to ponder. But glad its a sensor/indicator problem and not a true overheat problem. Keep us posted on what you find.Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackI used a tee fitting where the oil pressure sender connects to the engine and connected the pressure sender and the temperature sender to the tee. While I may not be getting an actual sump temp,I now know what the normal guage reading is and therefore I will know if the temp is getting too hot.
I think it’s nice to be able to monitor the temp even and though it may not be absolutely 100% accurate, you can see a trend and be aware of any developing overheating problem.
On a VW site online I saw a temporary fix to monitor engine temp and one guy made it a permanent installation, by inserting a wireless remote reading meat thermometer into the oil dipstick hole and mounting the gauge on his dash, with the sensor in the storage space behind the seat – his own homemade dipstick temp gauge. Taking something from the kitchen or the grill and sticking in your car? I don’t think the wife would approve, but it worked OK.John Muir had his own technique for checking Beetle engine temps. Alas, it’s not in the current editions of “The Volkswagen For The Compleat Idiot”.
It’s a Goldilocks technique.
Drive the car until the engine is up to operating temp.
Put your hand on the dipstick.
If it is comfortable the engine is running cold.
If you can’t touch it, the engine is too hot.
If you can just hang onto it the temps are just right.
I went for a ride again today about 15-20 miles, 95 outside temp, and my dash gauge (from Classic Instruments) after about 5 miles into the ride when the engine warmed up, went over the 230 mark, maybe to 240-250. I tested the resistance of the thermistor temp probe in the oil relief plug hole when I got home, and it read about 220 ohms. I get no reading at all when it is cool, which may mean that it’s working, but I don’t know for sure. When I talked to a tech guy at CI he said their temp probes should read 2118 ohms at 70 degrees, 205 at 180. 86 at 230. All the other things I’ve read about testing these probes say there should be at least a 200 ohm change from cold to hot. Like most other products, sending and gauge units must be compatible, if not from the same manufacturer. In the next day or two I’m going to pick up a laser infrared thermometer and see if that tells me that this system I have now is reading accurately or not. I do not know what sensor is in there now, I may have to get one from CI with their 18mmx1.5 adapter to fit the VW.
My new question is – my car has about a 2’x4′ opening between the engine bay and underneath where the clutch and transmission sits, there is no firewall closing off the engine compartment. It seems counter-intuitive that this area should be closed off surrounding the engine, it would seem that the engine would run cooler with this open as you would think there would be more air flow over it and into the fan intake, but everything I’ve read says that this space should be closed off so that the airflow through the fan over the oil cooler is more efficient. I do have the skirt underneath the rear of the engine in place, over the
heater boxes and mufflers, but it is nowhere tight up against the rear
bodywork. Do the rest of you have this area open in front of the engine, or did you close it off (the area behind the boot in front of the engine)? . Do you think it makes any difference? I can easily fashion a piece of sheet metal across this area to block it off if that’s what’s recommended. I’ve read on some of the dune buggy forums that their engines, which are almost totally open, run hotter than those in VW cars, which have a closed engine compartment.
I also have plugs in the fan exhausts instead of the hoses that go to the heater boxes and I would think this would direct even more air flow over my oil cooler as it has no where else to go.
The last thing I have to check, if the infrared thermometer proves I’m running a little hot, is to check the fan/alternator pulley to see if it’s the right size as too large a pulley makes the fan turn slower. The alternator seems fine, putting out 14+ volts, but it would probably do that at anything above slow idle.
Let me know if your firewall area is open or you closed it off somehow. I’ll let you know about the laser thermometer.
Thanks.
P.S. My car’s a Fiberfab.mrlmd40766.7426851852
Marc,
It’ll be interesting to see what others do with the open area just in front of the fan housing. I posted that I was thinking about fiberglassing in screen door screen material. My concern was more of debris entering the fan. We’ll have to keep an eye out for replies.Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackMrlmd..In my opinion which may not be correct. I would not close off the front unless I could properly seal the top half from the bottom half of the engine. Take a look at how a VW beetle looks. They do have a firewall in front , but they also seal the engine in the compartment with a gasket. They draw cooler air down from the top, the fan sucks it in and diverts some of it over the oil cooler and out the front firewall (if it is a doghouse fan shroud) and the rest is blown over the heads and jugs and out the bottom below the gasket sealed area. I think the main thing you want to do is make sure you have all the original tin and I think you will be fine. My Fiberfab/CMC is open just as you describe. Again this is my own opinion, but I think if you close in front of the engine and do nothing else you could contribute to heat build up
Allen, I think there is an aftermarket screen that fits over the the fan shroud intake. I cant see using one on a standard beetle set up, but for those open fronts we have it looks like a plus.
http://www.chircoestore.com/catalog/product_info.php?cPath=8 8_98_109_115_124&products_id=3207&osCsid=rph2s5kpgi3 uf3h1mht1chukj1
They even put them on standard bugs. It keeps a rag that you use to check oil. apiece of insulation that you put on the firewall to keep it quieter inside the bug etc. Many engines have thrown up after ingesting a piece of debris. The last I heard was a plastic bag. $10 screen-$1200 engine……….sounds like a good bet to me.
Good point dbrock. I think I will put one on mine. Sounds like cheap insurance. I have run over those plastic bags in my truck and had them wrap around the exhaust and stink up a storm. On my td it stands a good chance of sucking into the fan. A member here the other day even mentioned the occasional hand check of the fan intake to make sure its clear. I do that once in awhile, but always give it inspection after it has set for the winter to make sure some rodent hasnt built a nest in there.
My ‘factory built’ VW based London Roadster has nothing in the area in front of the engine. It came with chrome aftermarket tin.It does not have a thermostat or fan intake baffle ring. The engine cover has an opening under the spare tire, stock VW wheel with wire hubcap. On the LR ,the splash pan and engine cover are one piece so the engine is not sealed off from exhaust heat at the rear,sides or front. I’m not saying that this is the correct setup , but I have owned the car since 1994 and have never had a problem with the engine overheating.I’m not telling anyone to build their car like this ,just saying it works for me. I drove it 175 mi on a 95 degree day with myself and my wife and the trunk FULL of vacation stuff with no problems.
That screen for the fan shroud looks like a really good idea to keep stuff like leaves or bags from being sucked up into the fan. It’s easier than putting a screen in front of the engine over that opening but that’s another option. I’ll be getting the laser thermometer tomorrow and check on what my temp really is, then maybe a replacement oil temp sensor from CI to match my gauge. This is like a boat money pit ’till you get it all right and the way you want it.
This screen makes a lot of sense, especially for $13.95. I don’t know how many times a stuck my hands around the fan shroud to clean leaves and debris out of the oil filter and air passages.
The screen pictured above is commonly used on sand rails and dune buggies. It keeps the big junk from being kicked up and picked up by the fan. However if you get a plastic bag sucked into the engine compartment the vaccume created by the fan could still suck it against the screen cutting off the air flow anyway. Leaves are a slightly different matter depending on their size.
Kinda makes you wonder about taking a nice fall day ride out in the country where huge maple leaves are all over the road doesn’t it!!!
I’d go for a ride on two lane, maple tree lined roads anytime. Grew up in that environment and loved every minute of it. But back then I didn’t have a VW…I had a 57 Chevy 2 dr. Life goes on…………….
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackI may get one of those but I’m also going to look for some sort of screen or mesh to put over the opening in front of the engine, probably just screw it on into the fiberglass or pop-rivet it (then you can’t get it off so easily if you have to remove it for any reason). On my way to pick up a laser thermometer at Harbor Freight.
I was about to order one of the shroud intake screens and discovered they only fit non doghouse shrouds. The early shrouds have a lip the screen will attache to. The doghouse shrouds do not have this lip. You could still fabricate a bracket to use the screen or simply screw or pop rivit some wire mesh over the fan intake opening on the later model shrouds. Just wanted to pass this information on before anyone ordered a screen that may not fit their shroud without modification.
I noticed that too, it won’t work on my car. I found a aluminum mesh grill at Home Depot that I am going to put over the front of the engine compartment to try and filter out stuff like that, to keep it from getting sucked into the fan. If a bag or a bunch of leaves got stuck on that screen it could possibly block off the whole intake into the fan.
I am also toying with the idea to hook up either a large enough diameter flexible hose or metal HVAC duct to the front of my fan intake and lead it either out to one or both sides of the car under the wheel wells or one piece angled/bent to extend forward underneath the car in front of the transmission away from the engine to draw in cooler air into the fan (with some sort of screen over the front of it).Just got 4 new 165/80 R15 tires today and they fit fine. This old car is getting newer by the day. Now I just need the old top repaired or get a replacement made. $600 from MGMagic seems like a lot of money, but that’s the price of having a toy. (They also sell it with side curtains, can’t buy the top alone),
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